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2 years ago

Cos (pi/11)+cos (3pi/11)+cos (5pi/11)+cos (7pi/11)+cos(9pi/11)

1 answer:

4 0

All you have to do is input these terms in a scientific calculator and you would immediately get the answer. However, you should note that the units are in radians. Therefore, make sure that your calculator is in the mode of radians before inputing. Then, you would get an answer of 1/2.

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What is (x+6)^2 and (x-3)^2

Snezhnost [94]

(x + 6)² (x - 3)²
(x + 6)(x + 6) (x - 3)(x - 3)
x² + 6x + 6x + 36 x² - 3x - 3x + 9
x² + 12x + 36 x² - 6x + 9

4 0

2 years ago

6 people will attend a lunch 2 cans of juice should be provided per person determine the total number of cans of juice required

N76 [4]

Answer:

Step-by-step explanation:

it's 6 people and 2 cans of juice goes to each person so you can multiply 6× 2 and you get 12 . 12 cans of juice would be required to provide 6 people with 2 cans each .

8 0

3 years ago

Calculate the sample standard deviation and sample variance for the following frequency distribution of hourly wages for a sampl

lidiya [134]

Answer:

(a) The sample variance is 16.51

(a) The sample standard deviation is 4.06

Step-by-step explanation:

Given

$\begin{array}{cc}{Class} & {Frequency} & 8.26 - 10.00 & 20 &10.01-11.75 & 38 &11.76 - 13.50& 36 & 13.51-15.25 &25&15.26-17.00 &27 &\ \end{array}$

Solving (a); The sample variance.

First, calculate the class midpoints.

This is the mean of the intervals.

i.e.

$x_1 = \frac{8.26+10.00}{2} = \frac{18.26}{2} = 9.13$

$x_2 = \frac{10.01+11.75}{2} = \frac{21.76}{2} = 10.88$

$x_3 = \frac{11.76+13.50}{2} = \frac{25.26}{2} = 12.63$

$x_4 = \frac{13.51+15.25}{2} = \frac{28.76}{2} = 14.38$

$x_5 = \frac{15.26+17.00}{2} = \frac{32.26}{2} = 16.13$

So, the table becomes:

$\begin{array}{ccc}{Class} & {Frequency} & {x} & 8.26 - 10.00 & 20&9.13 &10.01-11.75 & 38 &10.88&11.76 - 13.50& 36 &12.63& 13.51-15.25 &25&14.38&15.26-17.00 &27 &16.13\ \end{array}$

Next, calculate the mean

$\bar x = \frac{\sum fx}{\sum f}$

$\bar x = \frac{20*9.13 + 38 * 10.88+36*12.63+25*14.38+27*16.13}{20+38+36+25+27}$

$\bar x = \frac{1845.73}{146}$

$\bar x = 12.64$

Next, the sample variance is:

$\sigma^2 = \frac{\sum f(x - \bar x)^2}{\sum f - 1}$

So, we have:

$\sigma^2 = \frac{20*(9.13-12.63)^2 + 38 * (10.88-12.63)^2 +...........+27 * (16.13 -12.63)^2}{20+38+36+25+27-1}$

$\sigma^2 = \frac{2393.6875}{145}$

$\sigma^2 = 16.51$

The sample standard deviation is:

$\sigma = \sqrt{\sigma^2}$

$\sigma = \sqrt{16.51}$

$\sigma = 4.06$

6 0

2 years ago

Decrypt the word DKA if it was encrypted using an alphabetic Caesar shift cipher that starts with shift 5 (mapping A to F), and

pochemuha

Answer:

YET

Step-by-step explanation:

TO DECRYPT DKA USING THE CAESAR SHIFT CIPHER STARTING WITH 5 SHIFTS.

TO DO THIS DECRYPTION, WE'RE GOING TO LOOP THE ALPHABETS.

D = LOOPING THIS LETTER 5 TIMES, WE HAVE C - B - A - Z - Y.

SO, D IS DECRYPTED AS Y

GOING FURTHER, THE ENCRYPTION SHIFTS BY AN ADDITIONAL SPACE. THIS MEANS, IF THE FIRST "Y" WAS ENCRYPTED IN 5 SPACES TO GET D, AND AN ADDITIONAL SPACE WAS ADDED TO THE NEXT ALPHABET, IT BECOMES 6.

K IS THEN DECRYPTED AS

K = J - I - H - G - F - E

K IS DECRPYTED AS E

GOING FURTHER, THE NEXT WAS ENCRYPTED WITH AN ADDITIONAL SPACE EVEN MORE, SO, A IS DECRPYTED AS

A = Z - Y - X - W - V - U - T.

THUS, DKA IS DECRYPTED AS YET

5 0

3 years ago

What is 90 by 25% decreased

viva [34]

Answer:

- 22.5

Step-by-step explanation:

Answer:

90 decreased by 25% = 67.5

Absolute change (actual difference):

67.5 - 90 = - 22.5

8 0

1 year ago

Read 2 more answers